Oil Light on the Car Come On While Driving - Free Car Diagnostic

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Oil Light on the Car Come On While Driving

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When the oil light on the car came on steady while driving, the engine oil pressure is low. The reason is low-level engine oil, the oil pump is faulty, or the oil pressure switch and its wirings are faulty.



The oil is sent to lubricate the main bearings then sent to the crankpin passing through the crankshaft to lubricate the connecting rods. The oil is injected from the oil jets located at the bottom of the cylinder sleeve and squirts and blows against the pistons, piston pins, and cylinder walls to lubricate and cool.

The oil sent from the oil gallery to the valve mechanism passes through the inside of the rocker shaft and camshaft and lubricates the bushings of the rocker arm, the camshaft journal, the contact face of the cam and rocker arm, and then drops down into the oil pan. The gears are lubricated with oil injected from the oil jet from the oil gallery.

The reason why oil light on steadily while driving

1) The engine lacks oil or the oil level is low causing the car's oil light to come ON.
2) The Oil Pump is faulty.
3) The Oil Pressure sensor or its wiring is faulty.


If the oil warning lights on the dashboard came on steadily while driving, it is an indication of a serious problem with the car, there is not enough oil pressure inside the engine. When there is not enough oil pressure the engine will not be lubricated properly.

Car Troubleshooting

The first thing to do is to check if the engine has enough engine oil. How to check the oil in a car? Now open the hood and locate the oil dipstick. Check the dipstick if it indicates enough level of oil, see the car owner's manual if you are not sure how to check the engine oil level. If the engine oil level is low then the low engine oil is what triggers the oil light to come on steadily. The low oil level causes the oil pressure inside the engine to become low also. Once the engine oil is low, the oil sensor is triggered and causes the oil light to be lit.

How to Check Oil in Your Car
How to check the oil in your car? Start the car and park it on the level road, let it run until the engine reaches the operating temperature. Read more » How to Check Oil in Your Car


If there is enough oil inside the engine then the problem is not the amount of engine oil but most likely, the oil pump is faulty or the oil pressure and its wiring are faulty.

The lubricating oil in the oil pan is drawn up by the oil pump (drive through the oil strainer to filter large-sized foreign particles and then through the oil cooler oil filter to filter small-sized foreign particles, and sent to the main bearings and valve mechanism passing through the oil gallery.
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The oil gallery is equipped with an oil pressure switch or oil pressure sensor, and the oil pressure warning lamp and pressure gauge to inform the driver if oil pressure is indicating the specified value or not.

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The oil pump is the one that creates oil pressure inside the engine if the oil pump is defective the oil pressure inside the engine will drop which triggers the oil warning light to light.

The oil warning light responds to the signal it receives from the oil pressure sensor, now if the oil pressure sensor is defective the data of the oil pressure inside the engine will not correctly read, and many times it reads a low oil pressure and it will send an electrical signal to oil warning light to come on. This is also the same happen if the wiring of the oil pressure sensor that connects to the oil warning light is faulty or loose.

What to do?
If the engine Lacks Engine Oil. Add some amount of oil to the engine to make sure the engine is not overfilled.

If the oil pump is faulty or the oil pressure sensor and wiring is faulty

Bring the car to a shop and have a mechanic inspect the oil pump and the oil pressure sensor/wiring. It is not advisable to drive the car when this happens because it might cause the engine to freeze up.


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